Ted Cruz helped pay for his 2012 Senate race with $1 million in loans from Goldman Sachs and Citibank. He didn’t disclose this at the time, saying instead that he was financing his long-shot (and ultimately victorious) electoral effort with virtually all his family’s “personal funds.”

Senator Cruz, a Republican now running for president, revealed the loans later in Senate ethics reports, according to The New York Times, which plays this story high on its front page Thursday. But by then he was safely in office, having run as “a populist firebrand who criticized Wall Street bailouts and the influence of big banks in Washington,” writes the Times’s Mike McIntire.

The Cruz campaign argues that it matters not at all. The failure to disclose the loans in 2012 was inadvertent, Cruz officials argue. Since the loans were drawn against personal brokerage holdings, they really were, in essence, the family’s savings, runs their defense.

The legal implications are probably modest. It’s possible the Federal Election Commission may eventually fine Cruz for the omission, but if history is any judge, the amount won’t be stunning and the implied rebuke won’t be harsh. Financial disclosure law is arcane and routinely flouted, inadvertently and otherwise, by many candidates in the midst of a campaign struggle. Cruz did in the end disclose the loans, after all. He does not appear to have received any special favor or discount from the banks.

But as for the 2016 presidential race, the loan revelations could indeed make a difference. They’ve given the Cruz’s opponents new information with which to attack him at a crucial time. In particular, the story will let Donald Trump, Marco Rubio, and other rivals depict the Texas senator as inauthentic candidate, a GOP insider, a fake somehow – not the duck-hunting “populist firebrand” he tries to be.

Democratic operative David Axelrod jabbed this point home in a not-so-subtle reference about Cruz’s outsider image.

“Maybe @tedcruz’s million dollar campaign loan from Goldman Sachs will be bond with GOP elites,” cackled Mr. Axelrod in a tweet on Thursday morning.

Cruz is already in some trouble on this front, after all. Mr. Trump is hammering Cruz on the question of whether his birth in Canada to a Cuban father and American mother qualifies him as a “natural born citizen” able to run for president under constitutional strictures.

Trump professes to not know whether this is the case himself (most legal experts think Cruz easily qualifies) but says that Democrats will surely challenge Cruz in court. Thus the GOP shouldn’t risk putting Cruz forward as its nominee.

“Sadly, there is no way Ted Cruz can continue running in the Republican Primary unless he can erase doubt on eligibility. Dems will sue!” tweeted Trump on Wednesday.

Trump is portraying Cruz as untrustworthy, not one of our people. The loan story will give him more ammunition. This guy is in cahoots with Wall Street, Trump – or Senator Rubio, or some other rival – might say. He’s a Canadian banker! Probably wants to flood America with subsidized lobsters and maple syrup and take US jobs.

OK, that’s a bit over the top, but you get the point. If you think that won’t happen, consider that the discussion of Cruz’s citizenship appears to have blunted his momentum in Iowa polls, with the crucial state caucuses looming.

“Cruz supporters shouldn’t panic, but Trump’s attacks have moved the needle a bit. With a bit over two weeks to go, game on,” writes Neil Stevens Thursday at the right-leaning RedState site.

Of course, in many ways Cruz has the most obvious insider credentials of maybe any GOP candidate except Jeb Bush. Cruz was a high school valedictorian who attended two – count ’em, two – Ivy League schools, Princeton and Harvard Law. His wife worked in the investment management division of Goldman Sachs. He was an official in the George W. Bush administration.

It’s his attacks on the GOP establishment and his counter-warfare in the Senate that have won him outsider cred. He’s carefully drafted behind Trump, agreeing on many issues, such as Trump’s tough anti-illegal immigrant positions. The question now is whether the matter of a million-buck loan can dent that image.